Not everyone is as brash as Bert. Some folks are a little shy and may need some encouragement before they can be persuaded to sing in public. I have noticed, at some recent sings that I have attended, that these good folks get ignored. They get bypassed by the guitar hogs who cannot wait for their turn to come around. If there is a lull for more than a few seconds they jump in out of turn, and they do it again and again throughout the evening. Anyone who is polite or who may be a little shy doesn't get a chance to sing.

If you are organizing a sing in your area, don't forget these folks, they have talent but they are too polite to jump into the trough with both feet.
Make sure that you give them a chance to sing.

Bert.